The best way to describe Masahiro Tanaka's day was tentative progress.

Sure, he felt no discomfort Monday after throwing for the first time since reporting pain in his right elbow following his July 8 start. But based on what he and manager Joe Girardi said after the successful outing, it is abundantly clear that it will take more than a few soft tosses to give the Yankees' ace the all-clear.

"It's really light catch," Girardi said of Tanaka's day at the ballpark, which was made up of 25 60-foot throws on the Stadium's outfield grass. "There's still a really long ways to go. You have to plow through each step, really."

The progress:

"I'm very relieved," Tanaka said through his translator. "I think the plan is to increase the number of throws as well as the distance . . . I think it went well."

So there you have it: Although he has a partial tear of his ulnar collateral ligament, the decision to forgo Tommy John surgery in lieu of a platelet-rich plasma injection seems inspired . . . so far.

Subscribe to Newsday’s sports newsletter

Receive stories, photos and videos about your favorite New York teams plus national sports news and events.

Those last two words are key, because neither Girardi nor Tanaka is ready to say he can make a full comeback this season.

Tanaka, who received his injection July 14, said then that he felt discomfort doing everyday movements. "It's hard to make an assessment" on whether skipping surgery was the best approach, Tanaka said Monday. "Today was actually my first day throwing . . . but [my] mindset is just to go forward -- keep positive and go forward."

Girardi had said the number of tosses Tanaka is allowed to make will be increased gradually, and that he eventually will throw off the mound only if he continues to feel no discomfort. Tanaka is slated to have another tossing session Tuesday, and the Yankees plan to increase the distance, Girardi said.

"You look at this as the start, really," he said. "You have to get him on the mound and in competition. That's what you have to do to have a really good idea where you're at."

Although a best-case scenario has Tanaka returning to the club in September, both said it is too early to establish any timetable. If Tanaka were to return to pre-injury form, the Yankees certainly could use the boost. Before going on the disabled list, the 25-year-old rookie was 12-4 with a 2.51 ERA and a 1.01 WHIP.

The downside to bringing him back in September and risking further injury is huge, because surgery likely would knock him out for most if not all of 2015. It's a disturbing prospect for a team that signed him to a seven-year, $155-million contract.

"It's way too early to see," Girardi said. "Obviously, if there was discomfort, that would be very discouraging. It is a positive day."